The present invention relates to an apparatus adapted to assist the driver of a vehicle to maneuver the vehicle into a position that allows ease in coupling the vehicle to a trailer. More particularly, the present invention is directed to a ranging apparatus for aligning the respective hitch elements of the towing vehicle and a trailer vehicle while the driver is seated in the towing vehicle. Thus, the present invention is particularly useful to couple a bulky trailer that cannot easily be handled without the aid of a helper and is applicable to any type of trailer vehicle, especially camper-type trailers.
Recently, with the increase in both leisure time and mobility many individuals are finding enjoyment and relaxation by vacationing in a camping vehicle. Typically these vehicles take three forms. One such camping vehicle is the common camper wherein a camper shell is mounted to a small truck by positioning the camping vehicles or shell within the bed of the truck. In some instances, these campers are formed as an integral part of the truck. A second type of vehicle is a specialized vehicle wherein the driver is actually situated within the camping vehicles while driving. These vehicle range in size from vans to large, self-powered motor homes. The third type of vehicle is that of a trailer that is adapted to be towed by a tractor vehicle such as a car or truck. These camper trailers range in size from small, lightweight trailer frames having expandable canvas or tent-like structures to full-scale trailers sleeping a relatively large number of people.
One problem that is encountered when a vacationer selects a trailer camper, though, is the difficulty experienced in attaching the tow hitch of the towing vehicle to the mating tow hitch of the trailer, especially when this task is attempted without the assistance of another person. This problem results from the fact that it is often necessary to accurately align the hitch elements since the weight of the trailer vehicle prevents the trailer from being manually moved into the position for coupling with the tractor vehicle. Indeed, even slight errors of alignment of the coupling elements makes it difficult to attach the trailer vehicle to the tractor vehicle. Therefore, there is a need for a device that assists the driver in aligning the respective hitch elements as closely as possible.
The recognition of this problem, however, is not new and solutions have been attempted in the past. An example of one prior art device which sought to solve this problem is found in U.S. Pat. No. 3,363,318 issued Jan. 16, 1968 to Folkins et al. In this device an L-shaped bracket is attached to a post on the trailer vehicle and this L-shaped bracket has a forwardly projecting portion that mounts a pivotal signal lever slightly forwardly and above the ball socket of the trailer. A narrow rod extends vertically upwardly from the ball hitch of a tractor vehicle so that, if the tractor vehicle is properly positioned, the upward point of the vertical rod tips the signal lever to indicate that the hitch elements are aligned. A problem manifests in this device, though, where the driver of the tractor vehicle misses his mark since, in absence of the signal, the driver may back the tractor vehicle an excessive distance. In such event, the tractor vehicle can actually strike the towbar of the trailer vehicle thereby potentially causing damage to the tractor vehicle, the trailer vehicle or both.
Other prior art devices also describe structures to assist the coupling of a tractor and trailer vehicle. U.S. Pat. No. 3,818,599 issued June 25, 1974 to Tague discloses first and second telescoping rods mounted to the tractor and trailer vehicle, respectively, adjacent to their respective hitch elements. Each of these devices is secured by the mounting block having position adjustment means, with the rods being oriented somewhat vertically of the hitch elements. A somewhat similar structure is shown in U.S. Pat. No. 3,765,703 issued Oct. 16, 1973 to Voelkerding et al, wherein the vertical rods are positioned on the respective hitch elements of tractor and trailer vehicle with these rods having enlarged balls on their uppermost tips which balls touch to indicate an aligned condition. A problem in both the Tague and the Voelkerding structures, though, is that the respective signalling elements must always be mounted to the tractor vehicle, even after it is uncoupled from the trailer, which may be unsightly and awkward should the tractor vehicle be used for transportation after the trailer is uncoupled.
Yet another structure is described in U.S. Pat. No. 3,767,292 issued Oct. 23, 1973 to Rutkowski wherein a convex mirror is attached by a bracket assembly to the towbar of the trailer vehicle so that the driver may simultaneously view the ball socket and the ball hitch as the tractor vehicle is advanced towards the trailer vehicle. Disadvantages of this device include the distorted dimensional images provided by the convex mirror and the danger of breakage to the mirror from stones and road debris unless the relatively heavy and cumbersome mirror assembly is detached from the trailer vehicle after coupling. U.S. Pat. No. 3,418,628 issued Dec. 24, 1968 to Fenner discloses an electronic signalling assembly wherein three vanes are positioned side by side on the trailer vehicle with these vanes operative to close switches connected to visually perceivable lights. The center vane which corresponds to an aligned position for the hitch elements indicates an aligned condition whereas the left and right vanes indicate that the hitch elements have been positioned slightly out of alignment. Again, there is a problem should the driver of the tractor vehicle entirely miss the vane assembly so that damage may occur to the signalling apparatus, the tractor vehicle, the trailer vehicle, or any combination thereof.
Accordingly, and despite the structures provided by the prior art devices, there remains a need for an inexpensive alignment device which permits both longitudinal and side to side alignment of a tractor and trailer vehicle in a quick and convenient manner. There is further a need for such a device that is simple in mechanical operation requiring no electrical connections and which device may be readily removed when not in use. There is further a need for a coupling device that is adjustable for different vehicles, and which may be stored and then reset when the tractor vehicle is detached from the trailer vehicle.